Ischemic heart disease causes mitral regurgitation by the combination of ischemic dysfunction of the papillary muscles, and the dilatation of the left ventricle that is present in ischemic heart disease, with the subsequent displacement of the papillary muscles and the dilatation of the mitral valve annulus.
Dilation of the annulus of the mitral valve prevents the valve leaflets from fully coapting when the valve is closed. Mitral regurgitation of blood from the left ventricle into the left atrium results in increased total stroke volume and decreased cardiac output, and ultimate weakening of the left ventricle secondary to a volume overload and a pressure overload of the left atrium.
US Patent Application Publication 2007/0055206 to To et al., which is incorporated herein by reference, describes devices, methods, and kits for deployment of tissue anchors. In some variations, the devices comprise a shaft defining a lumen for housing at least one anchor therein (the anchor having an eyelet) and a mechanism for deploying the anchor distally from the lumen, wherein the inner diameter of the lumen is the same size or smaller than the diameter of the eyelet of the anchor to be disposed therein when the anchor is in an expanded configuration. In some variations, the methods comprise loading an anchor within a lumen of a shaft (where the anchor comprises an eyelet and the shaft has a slot therethrough), passing a linking member through the slot and through the eyelet of the anchor, and deploying the anchor. Other methods comprise loading an anchor within a lumen of a shaft, and deploying the anchor distally from the lumen.
US Patent Application Publication 2007/0080188 to Spence et al., which is incorporated herein by reference, describes systems and methods for securing tissue including the annulus of a mitral valve. The systems and methods may employ catheter based techniques and devices to plicate tissue and perform an annuloplasty. Magnets may be used for guidance in deploying fasteners from a catheter. The fasteners are cinched with a flexible tensile member.
U.S. Pat. No. 6,619,291 to Hlavka et al., which is incorporated herein by reference, describes a minimally invasive method of performing annuloplasty. A method for performing a procedure on a mitral valve of a heart includes inserting an implant into a left ventricle and orienting the implant in the left ventricle substantially below the mitral valve. The implant and tissue around the mitral valve are connected and tension is provided to the implant, in one embodiment, in order to substantially reduce an arc length associated with the mitral valve. In another embodiment, the implant is inserted into the left ventricle through the aorta and the aortic valve.
US Patent Application Publication 2006/0241656 to Starksen et al., which is incorporated herein by reference, describes devices, systems and methods for facilitating positioning of a cardiac valve annulus treatment device, thus enhancing treatment of the annulus. Methods generally involve advancing an anchor delivery device through vasculature of the patient to a location in the heart for treating the valve annulus, contacting the anchor delivery device with a length of the valve annulus, delivering a plurality of coupled anchors from the anchor delivery device to secure the anchors to the annulus, and drawing the anchors together to circumferentially tighten the valve annulus. Devices generally include an elongate catheter having at least one tensioning member and at least one tensioning actuator for deforming a distal portion of the catheter to help it conform to a valve annulus. The catheter device may be used to navigate a subannular space below a mitral valve to facilitate positioning of an anchor delivery device.
US Patent Application Publication 2007/0051377 to Douk et al., which is incorporated herein by reference, describes a catheter-based, annulus reduction device and system for cardiac valve repair and method of using the same. The system is usable for treating mitral valve regurgitation and comprises a catheter, a reduction ring carried within the catheter, the reduction ring including a plurality of exit ports formed in a side wall of the reduction ring and filament received in the reduction ring. The filament includes a plurality of radially extendible barbs corresponding to the sidewall openings. The reduction ring carrying the filament is deployed adjacent a mitral valve annulus and the filament is translated relative to the reduction ring to deploy the barbs through the exit ports and into the annulus and to further translate the reduction ring with deployed barbs to reshape the annulus.
US Patent Application Publication 2006/0025787 to Morales et al., which is incorporated herein by reference, describes methods and devices that provide constriction of a heart valve annulus to treat cardiac valve regurgitation and other conditions. Embodiments typically include a device for attaching a cinching or tightening apparatus to a heart valve annulus to reduce the circumference of the annulus, thus reducing valve regurgitation. Tightening devices may include multiple tethered clips, multiple untethered crimping clips, stabilizing devices, visualization devices, and the like. In one embodiment, a plurality of tethered clips is secured circumferentially to a valve annulus, and the tether coupling the clips is cinched to reduce the circumference of at least a portion of the annulus. Methods and devices may be used in open heart surgical procedures, minimally invasive procedures, catheter-based procedures, and/or procedures on beating hearts or stopped hearts.
U.S. Pat. No. 7,431,692 to Zollinger et al., which is incorporated herein by reference, describes an adjustable support pad for adjustably holding a tensioning line used to apply tension to a body organ. The adjustable support pad can include a locking mechanism for preventing slidable movement of the tensioning element in one or both directions. The locking mechanism may include spring-loaded locks, rotatable cam-like structures, and/or rotatable spool structures. The adjustable support pad may be formed from rigid, semi-rigid, and/or flexible materials, and may be formed to conform to the outer surface of a body organ. The adjustable support pad can be configured to adjustably hold one or more separate tensioning lines, and to provide for independent adjustment of one or more tensioning lines or groups thereof.
US Patent Application Publication 2007/0016287 to Cartledge et al., which is incorporated herein by reference, describes an implantable device for controlling shape and/or size of an anatomical structure or lumen. The implantable device has an adjustable member configured to adjust the dimensions of the implantable device. The implantable device is housed in a catheter and insertable from a minimally invasive surgical entry. An adjustment tool actuates the adjustable member and provide for adjustment before, during or after the anatomical structure or lumen resumes near normal to normal physiologic function.
US Patent Application Publication 2004/0236419 to Milo, which is incorporated herein by reference, describes methods for reconfiguring an atrioventricular heart valve that may use systems comprising a partial or complete annuloplasty rings proportioned to reconfigure a heart valve that has become in some way incompetent, a pair of trigonal sutures or implantable anchors, and a plurality of staples which may have pairs of legs that are sized and shaped for association with the ring at spaced locations along its length. These systems permit relative axial movement between the staples and the ring, whereby a patient's heart valve can be reconfigured in a manner that does not deter subtle shifting of the native valve components. Shape-memory alloy material staples may have legs with free ends that interlock following implantation. Annuloplasty rings may be complete or partial and may be fenestrated. One alternative method routes a flexible wire, preferably of shape-memory material, through the bights of pre-implanted staples. Other alternative systems use linkers of shape-memory material having hooked ends to interengage with staples or other implanted supports which, following implantation, decrease in effective length and pull the staples or other supports toward one another so as to create desired curvature of the reconfigured valve. These linkers may be separate from the supports or may be integral with them and may have a variety of shapes and forms. Various ones of these systems are described as being implanted non-invasively using a delivery catheter.
US Patent Application Publication 2005/0171601 to Cosgrove et al., which is incorporated herein by reference, describes an annuloplasty repair segment and template for heart valve annulus repair. The elongate flexible template may form a distal part of a holder that also has a proximal handle. Alternatively, the template may be releasably attached to a mandrel that slides within a delivery sheath, the template being released from the end of the sheath to enable manipulation by a surgeon. A tether connecting the template and mandrel may also be provided. The template may be elastic, temperature responsive, or multiple linked segments. The template may be aligned with the handle and form a two-or three-dimensional curve out of alignment with the handle such that the annuloplasty repair segment attached thereto conforms to the curve. The template may be actively or passively converted between its straight and curved positions. The combined holder and ring is especially suited for minimally-invasive surgeries in which the combination is delivered to an implantation site through a small access incision with or without a cannula, or through a catheter passed though the patient's vasculature.
The following patents and patent application publications, all of which are incorporated herein by reference, may be of interest:
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The following articles, all of which are incorporated herein by reference, may be of interest:
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